Originally Posted by Equilibrium Tuning
Theoretically you should be able to calculate the needed trim based on IAT by calculating the resulting variance in air density. I always thought IAT should be worked into a true speed density calculation. But in practice it doesn't seem that simple or consistent.
Almost by definition, an SD calculation has to use IAT (charge temp). PV = nRT. Nothing theoretical about it.
Do note, however, that most standalones aren't using a true SD or VE style fueling calculation, which calculates air mass available then fuel mass needed then injector on time. It's a more simple injector on time system, but still requires an air temp. compensation.